Brake



L. E. LA BRIE Nov. 17, 1936.

BRAKE Filed April 8, 1955 I-TIIIIIII Illllif Patented Nov. 17, 1936 BRAKE Ludger E. La Brie, South Bend; Ind., minor to Bendix Products Corporation, South Bend, 11111., a corporation of Indiana Application April 8, 1935, Serial No. 15,229 10 Claims. "(01. lac-79.5)

trated as embodied in an internal expanding automobile brake of the shiftable anchorage type.

An object of the invention is to provide improved means for adjusting a brake having two adjustments, one for each shoe. The illustrated brake comprises shoes individually connected by their respective adjustments to an intermediate portion of a thrust lever which fulcrums atone end when one shoe anchors and at the other end when the other shoe anchors, thereby dividing the thrust of the primary shoe between the anchored secondary shoe and the brake backing plate.

Whether or not this exact brake arrangement is used, an important feature of the present invention relates to means (preferably mounted on the backing plate and operable from outside the brake) for simultaneously operating the two adjustments, and which means does not interfere with the necessary shifting of the shoes and their adjustments.

The illustrated adjustment-operating means includes a novel device rotatably carried by the backing plate and having parts meshing with teeth formed on members which turn the threaded means of the two adjustments. The drawin also shows a novel and simple device for locking the adjustment.

The above and other objects and features of the invention, including various novel combinations of parts and desirable particular constructions, will be apparent from the following description of the illustrative embodiment shown in the accompanying drawing in which:

Figure 1 is a vertical section through a brake of the described typeTjust inside the head of the brake drum, and showing the brake shoes in side elevation;

Figure 2 is a partial section on the line 2-2 of Figure 1, showing the means connecting the shoes; and

Figure 3 is a partial section on the line 3-3 of Figure 1, showing the means for operating the adjustments from outside the brake.

The brake illustrated in the drawing is generally like that shown in Figure 5 of application No. 12,151, flled March 21, 1935, by Percy Edgar Hall, and it is not my intention to claim herein any subject-matter disclosed in said Hall application.

This brake includes a rotatable drum l0, cooperating with a support such as a backing plate l2 to form a substantially closed chamber or housing for the moving parts of the brake including the friction means which cooperates with the drum Ill. The friction means illustrated includes two shoes l4 and I6, connected at one side of the brake by novel adjustable thrust means described below, and having at the other side of the brake suitable anchorage and applying means.

The anchorage shown is a post I8 carried by the backing plate and arranged between the ends of the webs of the shoes, and preferably connected to the shoes by tensioned coil return springs 20 and 22, the spring 20 connected to the secondary shoe I 4 (i. e. the shoe which anchors in forward braking) being somewhat stronger than the spring 22 connected to the primary shoe It (i. e. the shoe which anchors only in reverse braking). A spring 24 is tensioned between the shoes to hold them against the novel connection described below. The direction of rotation of the drum II) for forward travel is indicated by the arrow in Figure 1.

The applying means illustrated includes a floating cam lever 28 cut out to clear the anchor l8 and which is arranged between shoe I4 and the backing plate. Lever 28 has at its lower end latorally-projecting thrust lugs 30 on opposite sides of the anchor and arranged between the ends of the shoes, and at its upper end has a side lug 32 engaged by the edge of -a lever 34 arranged beside the inner face of the backing plate and pivoted on the anchor I 8. The lower end of lever 34 has a return spring 36 connected to the shoe l6, and the upper end has connected thereto a flexible tension operator such as a cable 38 which extends through the backing plate and through a flexible conduit (not shown) to form part of a Bowden-type control.

The ends of the shoes opposite the anchorage and applying means are connected by a novel adjustable thrust device which includes a floating generally-radial lever 40. This lever is notched on opposite sides at its ends to engage fulcrums 42 and 44 formed on a stamped bracket 46 bolted or otherwise secured to the backing plate over an opening 48 therein. Thus the lever 40 rocks upon fulcrum 42 when shoe I4 is anchored, and upon fulcrum 44 when shoe I6 is anchored.

Each of the shoes is connected to the lever 40 by a novel adjustable thrust device including a socket 50 pivoted to the end of the shoe web, and a part 52 adjustably threaded at one end into the socket and having a rounded portion 53 at its other end which seats in a correspondinglyshaped seat in the lever 40.

Each part 52 engages lever 40 approximately midway between the other part 52 and the one of fulcrums 42-44 about which it rocks the lever when it applies the braking torque of the unanchored one of the shoes thereto with a servo effect.

approximately a cross between a full servo brake and a standard anchored shoe brake.

Each thrust part 52 is shown formed with an operating pinion or the like 54, with elongated teeth. Both sets of teeth 54 mesh with projections 55, in effect forming crown-gear teeth, from a rotatable member or plate 56 having a stem 58 extending through the opening 48. The stem 58 is squared or otherwise formed, to be gripped by a suitable tool, for turning member 56 about an axis passing through the center of lever 40, midway between the two sets of teeth 54. Thus turning stem 58 operates both of the adjustments simultaneously. The elongated teeth 54 can slide on the crown-gear teeth, as one shoe or the other anchors, without becoming disengaged 5,. therefrom.

, I' prefer to sleeve on the stem 58 a washer 60, covering the opening 48 and having a pawl 62 (Figure 3) yieldingly interlocked with one of an annular series of depressions 64 formed on member 56, by means such as a coil spring 66 sleeved on stem 58 and compressed between washer 60 and a flange or washer 68 seated in a groove in stem 58. I

While one illustrative embodiment has been described in detail, it is not my intention to limit the scope of the invention to that particular embodiment, or otherwise than by the terms of the appended claims.

I claim:

1. A brake comprising a stationary part, friction members on opposite sides of said part each of which has an adjustment adjacent said part, and means associated with said part for simultaneously operating both adjustments, and means associated with said part and said adjustments whereby only part of the braking force of one shoe is transmitted to the other.

2. A brake comprising friction members having a connection including two adjustments adjacent said members respectively, means for simultaneously operating both adjustments and means associated with the adjustments whereby only part of the braking force of one shoe is transmitted to the other.

3. A brake comprising friction members having a connection including two adjustments adjacent said members respectively, means for simultaneously operating both adjustments and means associated with the adjustments whereby only part of the braking force of one shoe is transmitted to the other, said connection being shiftable relatively to said means without disconnecting the adjustments therefrom.

4. A brake comprising an anchor and an adjacent applying device, shoes having said anchor and said device acting on their ends at one side of the brake, a connection between the ends of said shoes at the other side of the brake including two adjustments, one for each shoe, means for operating said adjustments simultaneously and which means does not interfere with shifting of the connection as one shoe or the other is anchored when the brake is applied and means associated with theadjustments whereby only part of the braking force of one shoe is transmitted to the other.

5. A brake comprising an anchor andv an adjacent applying device, shoes having said anchor and said device acting on their ends at one side of the brake, a connection between the ends of said shoes at the other side of the brake including two adjustments, one for each shoe, and means for operating said adjustments simultaneously and which means does not interfere with shifting of the connection as one shoe or the other is anchored when the brake is applied, said connection also including a double-acting lever connected to the shoes by said adjustments.

6. A brake comprising an anchor and an adjacent applying device, shoes having said anchor and saididevice acting on their ends at one side of the brake, a connection between the ends of said shoes at the other side of the brake including two adjustments, one for each shoe, and means for operating said adjustments simultaneously and which means does not interfere with shifting of the connection as one shoe or the other is anchored when the brake is applied, said connection also including a double-acting lever fulcruming at one end when one shoe anchors and at the other end when the other shoe anchors and connected between its ends to said shoes respectively by said adjustments.

7. A brake comprising an anchor and an adjacent applying device, shoes having said anchor and said device acting on their ends at one side of the brake, a connection between the ends of said shoes at the other side of the brake including two adjustments, one for each shoe, and means for operating said adjustments simultaneously and which means does not interfere with shifting of the connection as one shoe or the other is anchored when the brake is applied, said connection also including a double-acting lever fulcruming at one end when one shoe anchors and at the other end when the other shoe anchors and connected between its ends to said shoes respectively by said adjustments, the adjustment connecting each shoe to the lever being so arranged that when the opposite shoe is anchored it engages the lever between the then fulcrumed end of the lever and the adjustment connecting the lever to said opposite shoe.

8. A brake comprising shoes having anchorage and applying means at one side of the brake and a connection at the other side of the brake, said connection comprising a generally radial lever having at its opposite ends fulcrum means each preventing the lever from moving in one direction but permitting it to move in the other direction, and two threaded adjustable devices connecting the lever between its ends to said shoes respectively and each having operating teeth, in combination with an operating device extending to the exterior of the brake and which is rotatable about an axis at right angles to the brake plane and approximately midway between the two sets of operating teeth, and which has parts inside the brake operatively engaging said two sets of operating teeth respectively on opposite sides of said axis.

9. A brake comprising shoes having therebetween a connection comprising a generally radial .lever having at its opposite ends fulcrum means shoes respectively and each having operating teeth, in combination with an operating device adjustment, in combination with an operating deextending to the exterior of the brake and which vice for said adjustment including a rotatable is rotatable about an axis at right angles to the member inside the brake over said opening and brake plane and approximately midway between formed with an annular series of depressions and the two sets of operating teeth, and which has provided with an operating stem extending 5 parts inside the brake operatively engaging said through said opening, and a washer yieldingly two sets of operating teeth respectively on oppomounted on said stem and engaging the outer side site sides of said axis. of the backing plate and which has a pawl ex- 10. A brake comprising a backing plate formed tending through the backing plate and yieldingly with an opening and having friction means interlocking with one of said depressions. 10

mounted thereon and which means includes an LUDGER E. LA BRIE. 

